Adjust stack depth about log15 HOT 5 CLOSED

What does your wrapper do? Can it be achieved by a Handler instead?

from log15.

It provides an adapter from the log4go API (which takes Sprintf type strings). We're a big project, switching from that to log15. It means the bulk of our code can depend only on our internal log package.

from log15.

Adding a method to the Logger interface would require a new API version (log15.v3) and I agree it would be a shame if we were to clutter the interface for this reason.

It would probably be OK to add a package scoped variable (guarded by sync/atomic) with an exported log15.SetStackDepth function to modify it. If the sync/atomic is prohibative we could document that SetStackDepth must be called before any logging is performed.

from log15.

Some parts of our code will use log15 directly (structured logging!), and some through the wrapper (to keep older code working), so a package-level wouldn't work.

Having spent a bit more time with log15, I can do it with a handler like you suggested. The approach is the same as CallerStackHandler:

func addCaller(r *log15.Record) {
        callers := stack.Callers().TrimBelow(stack.Call(r.CallPC[0]))
        caller := fmt.Sprintf("%v", callers[0])
        if strings.HasPrefix(caller, "nlog.go") { // Trim this package
                caller = fmt.Sprintf("%v", callers[1])
        }
        r.Ctx = append(r.Ctx, "caller", caller)
}

The disadvantage is calling runtime.Callers again. If Record.CallPC was a 2 array, I could use that. But that's an optimization, and I don't have any numbers, so I should be good for now. Thanks for your help!

from log15.

I'm glad you found a work around.

It's not ready for production yet, but you might want to keep an eye on the log package in https://github.com/go-kit/kit. Its design draws heavily from lessons learned with log15, and I think the way we implemented recording caller information in that package supports the use case you have described here. Disclaimer: I contribute to both log15 and Gokit.

from log15.